s1_read_last_two_bytes_of_a_mbr_backup_file(){
	local file_path=$1
	local last_bytes=$(tail -c 2 "$file_path" | od -A n -t x1 | tr -d ' \n')
	if [ "$last_bytes" = "55aa" ];then

		echo "YES"

	else

		echo "NO"

	fi
}

s2_read_mbr_partition_table_info(){
	for i in {0..3};do
		offset=$((446 + i * 16))
		start_sector=$(dd if="$1" bs=1 skip=$((offset + 8 )) count=4 2>/dev/null | od -t u4  -An | tr -d ' \n')
		if ! [[ $start_sector =~ ^[0-9]+$ ]];then

			continue

		fi
		if [ "$start_sector" -eq 0 ];then

			continue

		fi
		size_sector=$(dd if="$1" bs=1 skip=$((offset +12)) count=4 2>/dev/null | od -t u4 -An | tr -d ' \n')
		end_sector=$((start_sector + size_sector -1))
		echo "$start_sector $end_sector"
	done

}

s3_parse_partition_info(){
	fdisk_output=$(cat)
	disk_size_bytes=$(echo "$fdisk_output" | grep "Disk /dev/vda:" | awk '{print $5}')
	disk_size_sectors=$(echo "$fdisk_output" | grep "Disk /dev/vda:" | awk '{print $7}')
	physical_sector_size=$(echo "$fdisk_output" | grep "Sector size" |awk '{print $4}')
	first_partition_start_sector=$(echo "$fdisk_output" | grep "/dev/vda1" | awk '{print $3}')
	first_partition_end_sector=$(echo "$fdisk_output" | grep "/dev/vda1" | awk '{print $4}')
	first_partition_type=$(echo "$fdisk_output" | grep "/dev/vda1" | awk '{print $8}')
	echo "disk size in bytes:$disk_size_bytes"
	echo "disk size in sectors:$disk_size_sectors"
	echo "physical sector size in bytes:$physical_sector_size"
	echo "first partition start sector id:$first_partition_start_sector"
	echo "first partition end sector id:$first_partition_end_sector"
	echo "first partition type:$first_partition_type"
}

s4_run_passwd_as_plain_user_and_get_status(){
	oversleeping_path=$(which oversleeping)
	chown root "$oversleeping_path"
	chmod 4755 "$oversleeping_path"
	oversleeping &
	ps -o uid,euid,ruid -C oversleeping | awk 'NR >1 {print $1","$2","$3}'	
}

s5_add_a_scheduled_task(){
	touch "$HOME/test_crontab";
	echo "*/5 * * * * date +\%Y\%m\%d_\%H\%M\%S >> $HOME/test_crontab" | crontab -
}

# 尝试触发机器人R3 by 张森